Can Muslims register for the military draft?

What registering actually involves

In the United States, almost all men aged 18 to 25 must register with the Selective Service System, including many non-citizen residents. There has been no actual draft since 1973. Registering just puts your name on a list in case Congress ever brings conscription back. Not registering can cost you some government jobs and state benefits and, for immigrants, can complicate citizenship. Some European countries, such as Finland, Austria and Greece, have active conscription with civilian alternatives.

Keeping your agreements

When you live in a country, and especially when you take its citizenship, you accept its laws. The Quran says:

Registering is a simple legal act that doesn't involve anything haram, so most scholars say Muslims should comply. See Do I have to follow the laws of my country as a Muslim?

What if a draft actually happens?

That is a separate question. If a draft were ever started, a Muslim would then think about the war itself and his own role:

• Defensive or just causes: many scholars allow serving.
• Wars you believe are unjust: you can apply as a conscientious objector or ask for non-combat service.
• No unlawful orders: obedience is only in what is right (Sahih al-Bukhari 7257).

Scholars differ on modern wars, so take advice if that day ever comes. See Can I join the army as a Muslim?

Women and the draft

In the US, only men currently have to register, though this is debated in Congress. In Islam, fighting is not an obligation on women, but women did serve as nurses and helpers in the Prophet's ﷺ time, so non-combat service is a familiar idea.